Filtering apparatus



March 7, 1933. v H wlTTEMElER 1,900,476

EILTERING APPARATUS Filed Sept 9, 1929 fnvento r:

her

A Q n Patented Mar. 7, 1933 UNITED STATES;

NEW YORK PATENT oFFIcn' HANS wrrrnmmna, OFIQERLINGIRUNEWALD, GERMANY, ASSIGNOR To MIDWEST MANUFACTURING COMPANY, 1N0, orv LOUISVILLE-KENTUCKY, A CORPORATION or 1 FILTERING APPA T S a lication filed se nars, ieaa se ia No. 391,41 and in Germ an y betober 27, 1928,

My invention relates to filtering apparatus for gaseous fluids and more particularly to filtering apparatus of the type in which the .filters consistof grids or screens. I

It is an object of my invention to improve a filtering apparatus of this kind with a View to permit extraction and inspection of the filters without interfering with the operation of the filtering apparatus.

To this end I subdivide the filters into a plurality of units, each unit having a frame, and this frame being provided with faces serving as sliding surfaces for the several units, and also as packing surfaces for obtaining a tight fit of the units with'the frame of the filter.

l/Vith filtering apparatus of the kind referred to, several grids or plates of sheet metal which are perforated in the manner of a grid or screen are superimposed to form a cell, preferably in such arrangement that the holes and the solid bridges of the grids or screens are staggered. In this manner, a labyrinth is obtained in which the gaseous medium is reflected and broken at an infinite number of angles and obstacles so that the dust is completely separated. The action of such a filtering apparatus may be improved by reducing the width of its open spaces toward the rear of the filtering apparatus, that is, decreasing the width gradually from the entrance to the It has been proposed to space apart theseveral filters so that they can be extracted separately and without interfering with theothers, but in this case a valve or damper must be provided for closing the gap which is formed by the extraction of the filters so that filtered airi'will not flow through the gap. Such means are comparativelyexpensive and complicated but still they do not effect a complete closure.

It. will be understood that in the types of 55 filtering apparatus aforesaid it was not practicable to extract a filter or several filters with out lnterfering with the operation of the filter, or without necessitating the complete shut-down of the filter. U r Y, 'Thesedrawbacks are overcome in my novel filtering apparatus and at the same time the filtering apparatus is improved in other res spects so that its operation is facilitated and a its initial cost is reduced. These advantages are particularly important in View of the fact that filtering apparatus for gaseous fluids are i r V used'for many purposes and therefore it is important to manufacture them production basis. I V

.In the drawing aflixed to this specification and forming part thereof a filterin'g a'p' paratus having filters arranged'inunits ac} on a quantity a cordingto my invention, isillustrated dial- 7%;

grammatically by way of example. y

the 'drawing, a, a are twoffiltering chambers shown in section. The chambers are. closed at. the top I and at, the bottom but are open at their front and reariends. The

may be arrangedfin any suitable po'sitionias required. r Q

bare the filters, which are grlds or screen's.

ters is combined into a unit in a holderv 0 with a handle (Z. It willbe understood that in this manner each unitconstitutes a separate layer of, filters. 'Air flows through the: unit in the direction indic'ate'dby the arrows, theair' to be filtered entering at'the"lower face'of each unit, andthe filtered air,being?" discharged at the upper face.

h isa frame in each chamber a, a,'g-isa' top'plate on the framewhich is cut out to 3 permit free passage of the air, and is adapt ed to be abutted against by the holder e of the top unit i are supports below the several units, and: 'f, are springs. on the support.

filters are shown in inclinedposition ,but

as described and anydesired number-offil-' m which exert-upward, pressure -011 the lowest holder 0. In this manner the units are held of the unit cause very little friction'at'the" faces of their own frames, at the top plate 9, and at the springs f. With the units in" an inclined position as illustrated the upper units would move downwards when one, of them is removedat the bottom of the filter and gaps would form at the top or at the- 2 sides of the apparatus through which uncleaned air mightflow to the exit. This is prevented by the springs f which, as is shown for the rear spring in the upper chamber a, immediately rise at the rear of a partly ex tracted unit and support the units above, so

that the top unit is always held engaged with the top plate 9. In this manner, the means referred to inthe introduction for prevent: ing flow of unfiltered air through the apparatus, are rendered unnecessary. and the ap-: paratus remains tight when its units areexchanged; 7 When the unitat the bottom has been extracted, a clean unit is-inserted at the top, and in this manner the units are gradually exchanged and replaced'by cleaned ones without in any way interferring with the'operation'of the apparatus. 7

It is understood that the holders 0 need not extend all round the filters of a unit but only parts of a holder may be provided for keeping the filters in the proper position with respect to each other and for presenting surfaces on which the units slide with respect to each other and to the top plate 9. The

top plate has been shown as a complete frame. of channel section but obviously any other section may be provided, and the top plate,

like the holders 0 of the unit, need not be a complete part.

surrounding said set, said holders being adapted to slide, and to fit tightly, in said frame and on each other, and means for exerting an upward pressure on the lowest holder.

2.,A filtering apparatus comprising a frame, filtering units in said frame, each unit including a set of filters and a holder surrounding said set, said holders being --'adapted toslide, and to fit tightly, in said frame and on each other, 'and a spring arranged in a fixed position with-'respectto said frame and-adapted to exert an upward pressure on thelowest holder.

In testilnony whereof I afiixmy" signature.

HANS WIfITEMEIER. Y

I wish it to be understood that I do not; I

desire to be limited tothe exact details 'of construction shown and described for obvi-L ous modifications will occur to a person skilled in the art. I V In the claims affixed to this specification no'selection of anyparticular modification of the invention is intended to the exclusion;

of other modifications thereof 'andthe right to subsequently make claim to anymodificags 'tion not covered by these claims is expressly reserved.

I claim z.- v i 1. A filtering. apparatus comprising a frame,filtering units in saidjframe, each i iunit including a set of filters-and a holder 

